Cooled mounting plate for electronic equipment



P. R. HUGHES 3,048,374

cooEEn MOUNTING PLATE EOE ELECTRONIC EQUIPMENT Aug. 7, 1962 2 Sheets-Sheet 1 Filed NOV. l0, 1958 INVENTOR A? 06f/5s Aug. 7, 1962 FIIed Nov. 1o, 195s P. R. HUGHES 3043,3 74

cooLEn MOUNTING PLATE FOR ELECTRONIC EQUIPMENT 2 Sheets-Sheet 2 Jin UnitedStates @arent 3,048,374 COOLED MOUNTING PLATE FOR ELECTRONIC E UIPMENT Paul R. Hughes, Englewood, Ohio, assigner to United Aircraft Products, Inc., Dayton, Ohio, a corporation of Ohio Filed Nov. 10, 1958, Ser. No. 772,768 3 Claims. (Cl. 257-256) brazed or otherwise united to an integrated form and which provi-des a fluid owing circuit for the absorption and carrying off of generated heat.

Another object of Ithe invention is fto utilize a unique means. of mounting the electronic or like equipment upon the plate for maximum heat transfer elect.

Other objects 4and structural details of thekinvention will appear from the following description when read in `connection with the accompanying drawings, wherein:

FIG. 1 is a view in perspective of `an electronic equipment package utilizing a mounting plate in accordance with the illustratedembodiment oi the invention;

FIG. 2 is a View similar to FIG. l showing the mounting plate structure in connection with a superposed bulkhead forming `a part of the equipment package;

FIG. 3 is a diagrammatic View ofthe mounting plate and a iin arrangement therein obtaining differential heat transmission;

FIG. 4 is a view similar to FIG. 3, but in structural terms;

FIG. 5 is `an end View of the plate of FIG. 4;

Y FIG. 6 is a fragmentary View in cross-section taken substantially along the line 6 6 of FIG. 4; and

FIG. 7 is ya fragmentary enlarged view in section of a button or stud interconnecting elements of the mounting plate and di-rectly mounting the electronic or like equipment. Y

Referring to the drawings, in its illustrative embodiment the invention is a part `of `an electronic package including 4a cylindrical case 10 closed at one end and open at the other to receive the mounted assembly of electronic components, .the inserted assembly including an end bulkhead v11. yA,sealedconnection effected between the "case,l 1t) `and bulkhead 11 in ya manner to close the interior Iof the case from outside communication. The pressure within the case accordingly can be maintained at 4any desired level Aagainst rising and falling exterior pressures. The bulkhead 11 is formed with a variety of access holes 12 for the making of electrical connections, and further with diametri-cally opposed openings 13 and 14 for connection in a system circulating a uid coolant.

The mounting plate of the illustrated embodiment of the invention is la unitary sub-assembly which is welded or otherwise secured to the bulkhead 11 to project from the inner face thereof in the manner indicated in FIG. 2. Comprised in the .sub-assembly is a pair of aligned, spaced apart flat metal plates 15 yand 16 of rectangular configuration. The plates detine therebetween a space 17 which is open at its upper and lower marginal edges i (as viewed in FIGS. 4 and 5) `and closed at its front and back marginal edges by inserted nose pieces 18 and 19. Installed in and assisting in holding the plates 15 and 16 in laligned spaced relation are ybuttons 21 which extend transversely through the space 17-'and relatively small diameter por-tions received in openings of cor-responding size in the respective plates, the opposite ends` of the buttons terminating substantially in the planes of the outer surfaces of the'plates. The buttons 21 serve also 3,048,374 Ibatented Aug. 7, 1962 as mounts for pieces of electronic equipment and so are variously distributed over the surface of the plate assembly. the buttons Z1 `are selectively drilled through or tapped to enable a Hush mounting of the electronic equipment with the plate as represented Iby the upper one of the plates 15 or 16. In this connection, it will be understood that the plate assembly `a-s described provides a mounting ibase for the electronic equipment and one or both sides thereof will in the use of the plate directly receive the installed equipment.

The upper and lower marginal edges of the space 17 are closed by respective manifolds Z2 and 23 which are directly supported on Iopposed longitudinal edges of the plate yassembly in the manner shown in FIG. 5. The manifolds are-closed at their one ends and are correspondingly arranged so that the opposite or open ends thereof communicate with respective fluid connections 13 and 14 in the bulkhead 11. According to the con-y struction and arrangement of parts, the connection 1'3 serves as the iluid inlet while the connection 14 serves as a ti-uid outiet. Thus, la iiuid is directed under pressure to inlet 13. Passing through the bulkhead, it is admitted to manifold 22; of the cold plate assembly within case 1li. 'Fhere it collects and descends through the space 17 between the plates 15 and 16. Flowing in this manner to lower manifold 23, the fluid leaves the cooling package by way of outlet 14. Flow of the fluid through the space 17, it will be understood, cools the plates v15 and 16, with -a consequent labsorption or dissipation of the heat generated lby the electronic equipment. The buttons 21, it may be noted, `are directly interposed in the path of the flowing iiuid and tend to conduct heat directly from the source to the owing iluid.

A iin material is arranged in the space 17 to provide extended heat transfer surface. The tin material is in the form of strips of a corrugated metallic foil-like mtaterial, and, as' ya simplified means of putting into effect a concept of variable tin density, is here used in a nurnber or" individual strips 24-28. rI'hus, as indicated in a comparison of strips 27 and 2S the folds thereof occur in diierential numbers per inch of length with the resultAV rto present iin area of ditiferent density along its own length, the strip 28 being so formed. The selection of the ndensity and the Iarrangement of the iin materiall in the space 17 is in this instance determined by the characteristics of the heat load. Thus, where on account of the arrangement ofthe electronic equipment the generated heat load is the greatest, then the n material is at that .point constructed land arranged for a maximum heat pick-up. Similarly, the invention :has in view restricting uid flow through the space 1'7 in a variable manner in 4accordance with the characteristics of the heat load. In thc illustra-ted instance, two `baiies 29 and 31 are arranged in approximately the middle of the space 17 and incline toward one another to define -a restricted opening 33; VFl`he incoming fluid from manifold ZZ accordingly is compelled in large part to follow a path downward along the sides of the space 17, these areas being in the present instance the ones in which the heat generated is the greatest. In this regard, in the illustrated form of lthe invention additional heat transfer surface in the Iside tareas Eof the plate is obtained by mounting on the exterior of the plate `16 assemblies 33 and 34 of external tins. An electronic package as disclosed may include an interior fan `blowing air Within the case over the electronic equipment and over the lin assemblies Further in accordance with the present invention,

acteert 33 and 34 `which assist -in conducting lthe heat in the moving to the plate.

Where necessary, las in the case of lin strip Z7, the iin material is formed with slots or openings 35 to allow passage of the buttons 211 therethrough. According to a further feature of the invention, these slots or open ings are constructed to leave an annular space around the buttons in such manner that the flowing `air in space 17 may make direct contact with the buttons and llow around them.

The entire lassembly comprising the plates 15 and 15, nose pieces 18 and 19, buttons Ztl, 1in strips Zit-2f, baflles 29 and 31 manifolds 22 and 23, and lin assemblies 33' and 34, :all are prelirninarily assembled, and while suitably lixtnred, are united into a single assembly, as by process of dip brazing. This assembly, which in greater or lesser part constitutes the mounting plate assembly, is then welded or otherwise attached to the rnain bulkhead 11 and in a similar manner attached to opposite strengthening webs or bulkheads if any. Equipment supporting brackets 36 and 37 similarly may be welded tothe plate assembly. The augmented assembly then is ready for installation of the electronic equipment, and the whole of the device is completed by being installed and sealed in the case 10.

FIG. 3 shows in diagrammatic form the arrangement of the lins several internal and external iins to correspond with the areas of high Aand low heat load. The references to yhigh and low heat load have, as noted, application to conditions of generated heat as determined by the kind and wattage lof the electronic equipment mounted upon the mounting plate, and the location thereof.

The mounting plate has its strength and its resistance to shear and sepa-ration stresses greatly increased by the buttons 21. Each of these, moreover, is formed with an annular groove '3S providing free flow area around the button Without loss of contact with the plates for eiective brazing. Thus, .as noted in FlG. 7, a representative button 211 is in elect formed with spaced apart flanges 39 and 41 in contact respectively with the plates 15 and 16 While the groove 38 delines open llow area close to the tapped interior 42 of the button.

What is claimed is:

l. A plate to mount electronic and like equipment,

including a pair of heat conductiing plate elements in parallel spaced apart relation, the space between said Aplate elements /being `open at certain marginal edges for electronic and like equipment and the lin material being constructed and arranged in spaced relation to said buttons to permit lateral passage of the buttons through the iin material without obstructing Huid llow around the buttons at the locations thereof, said buttons further being formed intermediate said plate elements with spaced apart `llanged contracting respective platte elements and made thin to expose the major part of the button intermediate the plate elements to contact with the flowing duid, said flanges being wide in relation to the Wall thickness of the button intermediate said plate elements, and manifolds mounted on the plate elements in enclosing relation to said certain marginal edges, said manifolds having respective lluid inlet and outlet openings, the assembly comprising said plate elements, said lin material, said buttons, said nose pieces and said manifolds being joined in ya unitary assembly.

2. A plate according to claim 1, characterized by external fins on said plate elements atselecti-on locations in correspondence with more intense heat loads upon the cold plate.

3. A plate to mount electronic and like equipment, including a pair `oi' heat conducting plate elements in parallel spaced apart relation and serving as a duct for flowing fluid therebetween, said plates having a plurality ot" aligned openings, a button installed in each pair of aligned openings having ends to tit `closely in respective openings in non-projecting relation to outer surfaces of said plates, said button having a bore opening through one end thereof `and through `the plate receiving said one end, said 'bore extending through the intermediate portion of the button or that portion intermediate said plates and defining relatively thin Walls in such portion, said intermediate portion of the button being formed with spaced apart radial ilanges for contact with respective inner plate surfaces, said flanges being made thin to expose a major part of the intermediate portion of the button to contact with the flowing tluid, and means providing extended heat transfer surface intermediate said plates and around said buttons, said means including iin strips having openings to pass. said 'buttons therethrough, said openings providing for a spaced relation of said tin strips and said buttons.

References Cited in the file of this patent UNITED STATES PATENTS v iwi- 

